DI press

DI press

(Digital Imaging press) A four-color digital offset printing press that uses lasers to thermally image the printing plates "on-press." DI presses provide better registration, broader color gamut with higher density, less dot gain and sharper details than traditional offset presses, where the plates are created "off-press" via exposure to film or on a computer-to-plate system (see CTP). DI presses accept only blank plates, and all four plates (CMYK) are simultaneously imaged with great precision. In addition, DI presses are waterless and do not require continuous ink-water balancing. Designed for fast make-ready and short runs, the entire operation is automated, from plate advancing to imaging, printing and cleaning.

The DI direct-to-press method was invented by Presstek, Inc., Hudson, NH (www.presstek.com), and the company licenses the technology to DI press manufacturers. In partnership with Presstek, Heidelberg was the first company to introduce a DI press in 1993. Initially using spark discharge technology for imaging, lasers were used in subsequent models. See CTP, digital printing, prepress and offset press.